Levin, along with other advisors, says that most of the planning he is doing now centers on reciprocal spousal trusts for estate planning. Clients can still transfer $10 million out of their estate that's not subject to estate tax.

John Dadakis, partner at Holland & Knight, a New York law firm, says, "If properly prepared, you will have these assets out of the estate and their growth out of the estate. There are ways you can take this money and still have it available."

The current estate exemption, $5.12 million, is the highest level in history. If Obama is re-elected, that number will likely fall to $1 million. That will give planners a three-month window at the end of the year to accelerate gifts and reduce their clients' estates.

A married couple can use $10.24 million between now and year's end. Some attorneys suggest that clients use that $10 million-plus to make gifts now and pass them free of gift tax. "Between now and December 31, you will see the biggest wealth transfer ever, no matter who wins," Handler says.

If you use that gift-tax exemption, your estate tax exemption will be zero. You will have gotten $10 million out. But you may have created other problems. For one, you no longer have that money. Another problem is that if you gift an asset, the receiver of the gift accepts it at the donor's "carryover basis," whereas an asset passed at death gets a "step up" in basis to its current value.

For clients who want to protect their estates from taxes, advisors like Brandon Jones, who works with Levin at Accredited Investors, have set up what they call "spousal access trusts," or "reciprocal trusts." These allow a couple to take $10.24 million out of their estate but still have access to it in two trusts, one set up for each spouse. The assets in either one can be tapped for certain needs such as health, education and maintenance for the spouse and children.

But these trusts must be constructed very carefully to meet the requirements for "indirect access," according to Jones and Dadakis. For instance, Jones says it won't pass muster to merely set up two trusts with opposite beneficiaries. You must have two different trustees.

"If I'm the husband creating the trust, my wife will be the trustee; to add a second trustee would be enough," Jones says. So, for example, for the wife's trust, she might name the husband and a son. "If I create a trust for Sarah and my son Sam, Sarah has access if we need some money to live on."

Dadakis says the trusts must be set up at different times, at least 30 days apart. Because most states, such as New York and Minnesota, do not have a gift tax, by setting up these spousal reciprocal trusts, "you will save $1.6 million in New York estate tax alone," Dadakis says.

His firm has been setting up these trusts all year. "But it's not so automatic that you can do it in a few days," he says. Jones, who says he has been "doing them heavily in the last two or three years," began using them in 2007.